102
Troubleshooting
Diagnostic procedure for check code
Check code
Operation cause
[b4]
1. Ps sensor error
Low pressure sensor (Ps) short circuit
2. Ps sensor connection error
3. Compressor error
Are the output voltage
characteristics of Ps sensor
normal ?
Check interface PC board.
Check compressor.
No
Yes
Are Pd sensor/Ps sensor
correctly connected ?
Check connection.
Pd sensor: CN501
Ps sensor: CN500
No
Yes
Yes
Is the low pressure below
0.95MPa during operation of
compressor ?
Sensor error
[
]
No
Check code
Operation cause
[b5]
1. External device error
External input display fault
2. Indoor PC board error
[b6]
External interlock display fault
Is the external device
operating normally ?
No
Is the external device connected
to connector CN17 ?
Check indoor PC board.
If defective, replace.
No
Yes
Yes
Check external device.
If defective, replace.
Check cause of the operation.
Check code
Operation cause
[b9]
Indoor pressure sensor short circuit
Output voltage error of indoor pressure sensor
There is an abnormal output voltage of indoor pressure sensor. Check connector (CN23) and output voltage
of the sensor.
If the sensor is normal, replace the indoor PC board.
14
Summary of Contents for A90-0132
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